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oxide7 writes "NASA launched a satellite featuring an brand-new instrument which will be able to measure the saltiness of Earth's oceans. Data from the Aquarius/SAC-D spacecraft will help scientists understand better the processes that drive ocean circulation and the movement of freshwater around the planet."

Spot measurements that do not encompass an entire ocean with a method that is inefficient, not automated, uses up thousands of gallons of fuel per month, ties up human resources, and gives out-of-date data,

or....

Use a satellite that can measure an entire ocean all at once via spectroscopy and map it in real time with computers.

And then your cubes will be concentrated by the currents in several zones, leaving large swathes of ocean uncovered. That's the problem with autonomous floating stations. It has been tried earlier for temperature measurement - it hasn't worked much better either.

Also, salinity can change as a result of storms, weather, etc. We'd like to watch it in realtime, which these cubes won't allow to do.

Is realtime ocean temperature important to you as well? No? Now think about weather forecasting.

Salinity drives ocean currents, which are important for climate. Do you want to know if a particular piece of land will have more storms in the next 20 years? Well, this satellite will help to predict such things.

Or use a satellite launched while we are bankrupt that can measure an entire ocean all at once via spectroscopy and map it in real time with computers. FTFY.

This would be all well and good if it was 1955, or if it was launched by the Chinese, but the simple fact is we're broke and the right would rather risk us defaulting than raise taxes to even 1990 levels. So spending on this kind of shit really needs to stop, at least until we can quit blowing cash like shit through a goose on three wars, new aircraft c

It's not just the right that feels we'd be better off defaulting but over 63 percent of American's according to a recent article. The initial poll indicated that over 45 percent feel that way but after they changed the questions and run the poll again, the answers resulted in over 60 percent response saying default and be damned about it.

Yes people in this country are getting tired of the ever growing debt due to the war and funding things like NATO (10billion per quarter), Israel (several billion per year)

If you think things are bad now just wait until the US starts defaulting on its debt. It's the quickest route I can think of to US becoming a second rate power. It will lead to a worldwide depression. If you think the 1930's were bad you haven't seen anything yet. I hope you have some sort of survivalist bolthole to retreat to if that happens.

Notice I got modded down for daring to say we're broke? I love how the MSM has put its fingers in its ears and goes "la la la everything is fine" instead of admitting we are in the start of a depression which anyone in the flyover states can plainly see.

Years of outsourcing and declining wages has left this country a third world nation, with a few at the top rolling in cash and the rest not able to keep their homes. if we looked at the ACTUAL numbers and not the BS the feds spread you are looking at 30% un

The NWS is going around fucking begging for fucking GOES replacements and those are the fucking sats we use to predict the fucking weather, you know, fucking hurricanes, tornadoes, droughts, etc? You know, the shit that affects our economy? And just like this, understanding how the ocean fucking works will help us understand what happens to fishing stocks and weather and a whole lot of other things so that we may FUCKING PLAN AHEAD FOR THE FUCKING FUTURE.

you are no doubt right, however there will be challenges either way. According to NASA scientist Gavin Schmidt a realclimate.org:
Aquarius retrievals are based on passive microwave technology and rely on the fact that salinity affects the thermal emission properties of the ocean surface. This effects are quite subtle, and the range of variability is relatively small, so it has taken many years for the technology to catch up to the need. This is however a first attempt to do this from space, so challenges

I tried to look up the mechanism of how microwave data is interpreted to give salinity levels, but all I could find in a quick hunt was some IEEE papers which were over my head. Anyone here care to give a summary of the method?

Salinity and temperature are the only things that alter the energies emitted and reflected by the ocean at certain centimetre wavelengths (frequency, 1.43 GHz). The atmosphere is almost transparent - no pesky gas, cloud or mostly rain. After that, you've got to model the galactic radiation which is also reflected and causes a lot of problems- luckily it's well known as it doesn't alter quickly very often.

BTW, the NASA Aquarius web site talks sheer nonsense that this is first salinity satellite. SMOS, laun

The instrument is a kind of radar called a scatterometer. It measures the amount of L-band (1400 MHz-ish) power reflected back by the ocean's surface. If you compare the amount scattered back in Horizontal and Vertical polarization, you can tell the dielectric properties of the water (mostly conductivity changes). In general, the reflection in vertical polarization (perpendicular to the surface) is more strongly affected b

"This mission is the most outstanding project in the history of scientific and technological cooperation between Argentina and the United States,"

That's why the acronym is SAC and not SSA (Satélite de Aplicaciones Científicas - Satellite for Scientific Applications). I think it's just another satellite... This was newsworthy in Argentina only because there are very few local satellites (I can only recall past iterations of SAC). Even the president talked [telam.com.ar] about this, "it is a matter of great pride for our people" (elections are near - the uranium enrichment facility is timed for 2 weeks before the presidential election's second round). But g

Quick question: where are the lines drawn between NASA's and NOAA's responsibilities?

NASA has much, much more satellite experience than NOAA so the responsibilities are often shared. On the other hand attempting to share "ownership" (as opposed to a single owner with well defined, shared responsibilities) led to a situation where a "White House Office of Science and Technology report concluded that NPOESS’ management structure was unsalvageable" (Warning: the provided link may have nothing to do with Aquarius...and may be entirely inaccurate...read with caution):
http://www.defenseind [defenseindustrydaily.com]

The last two climate satellites were lost due to "Launch Failures". One which was supposed to measure global carbon emissions at the highest resolution to date. I guess this one was not much of a threat to those who deny climate change.

The last two climate satellites were lost due to "Launch Failures". One which was supposed to measure global carbon emissions at the highest resolution to date. I guess this one was not much of a threat to those who deny climate change.

It's as big a threat to deniers as any satellite. It's just that the connection isn't as direct as some of the others. Understanding salinity and ocean surface temperatures are essential to understanding things like density, evaporation and how currents run which in turn affect the climate. The increase understanding will allow better accuracy for inputs into climate models which should improve their accuracy.

OK, just to clarify the article: the "collaboration" of Argentina in this project consisted in the design, construction, tracking, and operation of the satellite. The SAC-D is an Argentine satellite for the most part, built in collaboration with NASA and France, Italy and Canadian space agencies.

So the aquarius is an instrument on board of an Argentine satellite.

I think the measuring of salinity is a very cool project that could help understand global-scale weather. But the fact that a country considered a

If only... If only...Due to our typical third world/banana republic status:Yes, we have 2 nuclear plants working another in the making, 50 years in the making!yes, we have uranium mines and enrichment facilities, gathering dust thanks to dirty politicians doing what USA wants.We HAD ICBMs! project CONDOR-2, also shutdown by USA.Not to mention the lastest coup de etat, USA believes Argentina is gonna go commie like Chile and bam goes the coup...Our cars are mostly assembled with imported parts...Import of hi

It's SAC-D. Aquarius is the main instrument, built by NASA, while the rest sat was built in Argentina and tested in Brazil. The other instruments onboard are mostly Argentine but also Canada, Italy and France participated.

The Aquarius/SAC-D salinity-sensing instrument is not exactly brand-new. It is an L-band microwave radiometer based on the same principle as the one on the SMOS satellite launched in October 2009. Still, it helps to have more satellites monitoring the oceans.

Whenever I think of a spacecraft named "Aquarius," I think of the LM that the Apollo 13 astronauts used as a lifeboat to survive the trip back to Earth after their Service Module was damaged after launch. After delivering those astronauts safely back to LEO and being heroically jettisoned into the atmosphere to meet her demise, that spacecraft deserved to have its name retired.